1、 When Guizhou electric equipment company marks the line according to the conductor color

Black: internal wiring of devices and equipment.

Brown: the positive pole of the DC circuit.

Blue: negative pole of DC circuit; emitter of semiconductor triode; anode of semiconductor diode, rectifier diode or thyristor.

Yellow: phase a of three-phase circuit; base of semiconductor triode; control pole of thyristor and bidirectional thyristor.

Green: phase B of three-phase circuit.

Red: phase C of three-phase circuit; collector of semiconductor triode; cathode of semiconductor diode, rectifier diode or thyristor.

Light blue: neutral line or neutral line of three-phase circuit; grounding neutral line of DC circuit.

Yellow and green (each color is about 15-100 mm wide, alternately attached)

Ground wire for safety.

White: main electrode of bidirectional thyristor; semiconductor circuit without specified color.

Red and black parallel: an AC circuit connected by two core wires or twisted pair wires.

2、 When Guizhou electric equipment company selects the conductor color according to the line

AC three-phase circuit:

Phase A: yellow;

Phase B: green;

Phase C: red;

Neutral line or neutral line: light blue;

Safety ground wire: yellow and green.

AC circuit connected with twin conductor or twisted pair:

Red and black are parallel.